Is it permissible for a young man to chat with a non-mahram girl over the internet for the purpose of learning or teaching, taking into consideration that their interaction is formal and limited to questions and answers, and do the screen and large distances serve as a barrier (hijab) in this context?

The fundamental Islamic principle prohibits any relationship between a man and a woman who are not mahram (unmarriageable kin), unless it is strictly regulated by Islamic guidelines, such as avoiding private seclusion (khalwa), suspicious mixing, limiting interaction to what is necessary, and refraining from speaking in a soft or alluring manner.

If a woman asks about matters concerning her religion or worldly affairs that are unclear to her, there is no harm in that, for Allah Almighty says: "So ask the people of the message if you do not know" (Quran 16:43), and the Prophet, peace and blessings be upon him, said: "Seeking knowledge is an obligation upon every Muslim."

Therefore, seeking knowledge between the genders is not forbidden if it adheres to Islamic guidelines, provided that utmost caution is exercised and there is no risk of temptation (fitna).